TV out & windows media player

Hi, I can hook up my tv out from my computer and see everything perfectly on my TV. The only problem that I have is that windows media will play on my computer monitor but on the TV it is blacked out. I am sure its a media player thing. Is there a way around this? I watch internet TV but my provider only uses media player.

I had the same problem a while back, I am in a very vague mode tonight so forgive me.

I had a Geforce card which did the same, I had to go to display properties and click on the tab which has the overlay settings in it, in there was a setting which said full screen overlay device, it was disabled, i set it to secondary device and hey presto, perfect video.